title: Dimerization of tri(4-bromophenyl)benzene by aryl-aryl coupling from solution on a gold surface.
abstract: Monolayers of monomer 1,3,5-tri(4-bromophenyl)benzene (TBPB) and the dimerized product 3,3''',5,5'''-tetra(4-bromophenyl)quaterphenyl (TBPQ) on a gold surface have been studied using ambient scanning tunneling microscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Molecular layers are prepared by allowing sessile drops of solution to dry on a gold substrate. For room-temperature deposition we observe ordered arrays of TBPB in three distinct packing arrangements. Deposition on a heated substrate leads to the formation of the dimerized product, TBPQ, through a surface-induced aryl-aryl coupling. Regions of TBPQ coexist with regions of disordered multiply linked molecules. The conversion of monomer TPBP to dimers is confirmed using ToF-SIMS. Our results demonstrate an alternative, solution-phase approach to the formation of large molecules and nanostructures by coupling reactions.
authors.affiliation: School of Physics & Astronomy, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: James C
authors.initials: JC
authors.lastname: Russell
authors.forename: Matthew O
authors.initials: MO
authors.lastname: Blunt
authors.forename: Jason M
authors.initials: JM
authors.lastname: Garfitt
authors.forename: David J
authors.initials: DJ
authors.lastname: Scurr
authors.forename: Morgan
authors.initials: M
authors.lastname: Alexander
authors.forename: Neil R
authors.initials: NR
authors.lastname: Champness
authors.forename: Peter H
authors.initials: PH
authors.lastname: Beton
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D019281:Dimerization; D006046:Gold / Q000737:chemistry*; D008958:Models, Molecular; D012996:Solutions; D013499:Surface Properties
chemical_list: C559047:1,3,5-tri(4-bromophenyl)benzene; D001555:Benzene Derivatives; D012996:Solutions; D006046:Gold